Titanium-made cathode electrode for producing electrolytic copper foil, rotary cathode drum using the titanium-made cathode electrode, method of producing titanium material using titanium-made cathode electrode and method of correcting/working titanium material for titanium-made cathode electrode

Abstract

The purpose is to provide a cathode electrode for manufacturing an electrodeposited copper foil which is possible to be continuously and stably usable for a long duration of 3000 hours or longer to subsequently lessen the frequency of maintenance work execution as low as possible and to contribute to lower the running cost of the electrodeposited copper foil manufacture. As the means for achieving the purpose, a cathode electrode made of a titanium material is employed for obtaining an electrodeposited copper foil using an electrolytic copper solution and the titanium material having 7.0 or higher crystal grain size number and 35 ppm or lower initial hydrogen content is used for manufacturing the cathode electrode for manufacturing an electrodeposited copper foil. Further, also provided is a manufacturing method of the titanium material to be employed for the cathode electrode made of a titanium material.

Description

FIELD OF THE INVENTION[0001]The present invention relates to a cathode electrode made of titanium for manufacturing electrodeposited copper foils, a manufacturing method and a correcting method of a titanium material to be used for the cathode electrode made of titanium.PRIOR ART[0002]Conventionally, a cathode electrode made of titanium has been employed for manufacturing an electrodeposited copper foil. That is because a titanium material has a sufficiently stable acid resistant capability even to a strongly acidic solution such as a copper sulfate solution to be employed for manufacturing an electrodeposited copper foil and is easy to be handled as a cathode electrode owing to remarkably light weight as compared with a stainless steel or the like and easy to peel and separate the electrodeposited copper foil from.[0003]It is rational to require a cathode electrode made of titanium in a case of manufacturing the electrodeposited copper foil to be stable for manufacturing an electro...

AI Technical Summary

Benefits of technology

[0027]With consideration of this result, it can be assumed that the larger crystal grain size number or the smaller grain size the titanium material has, the less easy formation of titanium hydride or the less easy dropping of formed titanium hydride is provided.

[0091]Above all, in manufacture of a cathode electrode made of titanium for a manufacturing an electrodeposited copper foil with controlled existence ratio of twin in the crystal structure of 20% or lower, as described above, it is supposed that the possibility of twin appearance is high at the time of deformation of a titanium material and same results are observed as the results of the investigations which inventors of the invention have made so far. As described above, in the deformation of titanium, anisotropic crystal structure is accompanied with twin deformation and if the deformation temperature is increased higher than a room temperature, twin generation can be suppressed and consequently, it is made possible to suppress the increase of the twin density.

Problems solved by technology

At that time, depending on the micro shape of the shiny side, an excellent adhesion property to the etching resist layer cannot be provided, sometimes resulting in occurrence of the inferior finishing precision of the etching circuit.

However, actually, even if a titanium material excellent in acid resistance is employed for a cathode electrode, during the use for a long time, a phenomenon takes place that the surface state of the titanium material to electrodeposit copper thereon is changed with the lapse of time of electricity communication to make the surface roughened.

If the cathode electrode made of titanium is employed for manufacturing an electrodeposited copper foil while pits existing in the surface of the electrode, extremely small projections are formed or precipitation abnormality occurs in the shiny side of the electrodeposited copper foil in the points corresponding to the pits and in the case where a fine pattern circuit is to be formed by a further thinner etching resist layer is formed using so-called liquid resist, excellent registration becomes impossible.

For example, it becomes problems in the case where such an electrodeposited copper foil is employed for TAB (tape automated bonding) or for a rigid type printed circuit substrate with a wiring density of so-called 5 or more between pins.

Moreover, the grinding of a cathode electrode made of titanium to be employed for manufacturing an electrodeposited copper foil is difficult to be made full-automated and it requires a worker to have extremely high skilled level.

From a viewpoint of such circumstances, these facts results in increase of the maintenance cost of a cathode electrode made of titanium employed for manufacturing an electrodeposited copper foil and consequently results in increase of the running cost of electrodeposited copper foil manufacture as a whole.

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